Merge non-identical but the same authors or assign aliases

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which begins:

greenery wrote:

I have an author who shows up (on imported references – I didn’t enter these manually) as John Smith, J. Smith, J.R. Smith, John R. Smith, JR Smith, John Reginald Smith.

And this happens quite often.

Is there a way to merge these people into one? I sure hope so, but  I have searched here under ‘merge author names’ and many variations thereof without success. Can someone please give me a hint?